The anti-aging industry is expected to gross more than $291 billion worldwide by 2015

(<a href="http://www.health.com/health/" target="_blank">Health.com</a>)Hanneke Hops wasn't afraid of dying. What concerned her was growing old and not being able to run marathons, ride horses, or fly planes. So the 56-year-old Hayward, California, woman turned to Alan Mintz, M.D. -- a radiologist who founded the Cenegenics Medical Institute in Las Vegas, which specializes in "age management medicine."

She was prescribed recombinant human growth hormone (HGH), a synthetic version of a pituitary hormone hawked as a miraculous fountain of youth. Though the U.S. Food and Drug Administration (FDA) warns that taking HGH poses serious health risks, Hops -- unaware there was any harm -- began injecting it into her thigh six times a week.

She never did grow old. Six months later, in 2004, she was dead, her liver full of malignant tumors. While it is impossible to prove that HGH therapy contributed to Hops's death, the use of HGH has been linked to an increased risk of cancer. (Mintz said at the time of Hops's death that Hops would not have been treated if he knew she had cancer.)

Today, thousands of physicians are catering to the 78 million baby boomers who are hoping to feel younger, longer -- and willing to pay for the privilege. The anti-aging industry is expected to gross more than $291 billion worldwide by 2015.

The problem is, many of these so-called anti-aging doctors are making empty promises. "They're one step above snake oil salesmen," says Steven R. Goldstein, M.D., a professor of obstetrics and gynecology at New York University School of Medicine. They prey on women who have legitimate medical concerns such as poor sleep, flagging energy, and libido loss, he says, yet they often lack the training required to treat those problems.

Even worse, they peddle therapies -- most notably, the unapproved use of hormones like HGH and customized drug cocktails -- which are unproven and can even be deadly.

The rise of the anti-aging doc

Once, middle-aged women sought out a gynecologist for menopausal symptoms, or an internist for fatigue. Now a new brand of doctor is promising to treat the above, and deliver much more: better sex, a fitter body, dewier skin.

"They often try to convince people that aging is their fault: 'If you listen to us, we can fix the problem,' " says S. Jay Olshansky, Ph.D., a research associate at the Center on Aging at the University of Chicago.

Yet aging is a natural process, not a medical condition, and there isn't any therapy that can reverse it or slow it down, Olshansky says. Official medical associations from the Endocrine Society to the American Medical Association warn against using "anti-aging" interventions.

And while traditional doctors, such as endocrinologists (who specialize in hormones) and geriatricians (who focus on the elderly) are specifically trained to treat age-related conditions such as hormone imbalances, "not all anti-aging doctors have a degree or advanced expertise" in what they practice, Olshansky says.

In fact, anti-aging isn't a specialty that's recognized by the American Board of Medical Specialties, meaning doctors can't officially be board-certified in it. Yet it has its own professional society, the American Academy of Anti-Aging Medicine (A4M). Founded in 1992, A4M boasts some 24,000 members worldwide and offers a certificate in anti-aging medicine, available to any M.D.

Once a doctor sets up an anti-aging practice, she stands to make major profits. Many age-fighting treatments aren't covered by insurance, which means the M.D.s prescribing them are paid out-of-pocket, Olshansky says -- and that can add up to thousands per patient. At a time when physicians are getting lower and lower reimbursements under managed care, it's little wonder that doctors of all stripes, from emergency-room medicine to radiology, are flocking to this lucrative new specialty.

Unproven treatments

So how do you know if your doctor is making promises he can't keep? Here are the top dangers Health's investigation uncovered:

• Risky hormone therapies. The biggest weapon in the anti-aging doctor's arsenal is the willy-nilly prescribing of hormones. "The concept is that if you take a 60-year-old woman and duplicate the hormone environment from when she was 20, she'll feel like she's 20," says Nanette Santoro, M.D., director of the Division of Reproductive Endocrinology & Infertility at the Albert Einstein College of Medicine. "It is essentially the idea of drinking the blood of young children."

It's also hazardous, because most age-erasing doctors aren't trained in using these powerful substances. "In this entire field, I've only encountered one board-certified endocrinologist," says Thomas Perls, M.D., an associate professor of medicine and geriatrics at Boston University School of Medicine. "It's outrageous that people think they can prescribe these toxic hormone soups."

The main ingredient in that soup is HGH, which naturally declines in our bodies as we age. Anti-aging doctors claim that by boosting HGH levels with injections that can cost $12,000 or more per year, you can reduce body fat, build muscle, improve sexual function, and up your energy.

But "there is no scientific proof of this," Perls says. "And studies show that increasing HGH levels with drugs predisposes people to heart disease, diabetes, and cancer" -- suggesting that the hormone may have been a contributing factor in Hanneke Hops's death.

In fact, HGH is only FDA-approved for use in a handful of conditions in adults (including adult growth hormone deficiency, which is rare), and it is illegal to distribute a product containing HGH for anti-aging purposes.

Another hot hormone is bioidentical estrogen. For decades, women have relied on synthetic estrogen to relieve menopausal symptoms such as hot flashes and vaginal dryness. But when the Women's Health Initiative study on estrogen and progestin therapy was halted in 2002 -- due to a possible hormone-related increase in the risk of heart disease, stroke, blood clots, and breast cancer -- some doctors touted bioidentical versions, made from soy and yams, as safer (though there's no proof they're less likely to raise your disease risk).

Bioidentical creams and pills made by pharmaceutical companies are available via prescription and regulated by the FDA. Still, many anti-aging docs attempt to create their own bioidentical hormone cocktails tailored to their patients' special needs.

It's this customization that is most troubling to mainstream doctors. It involves taking a prescription to a compounding pharmacy, where pharmacists mix ingredients as outlined by your physician -- and the resulting concoctions are not approved by the FDA. "When the FDA looked at compounded medicines, 43 percent of them didn't have the things that they were supposed to," Goldstein says. That means the drug you're getting may not work -- or may have unpredictable side effects.

Whether there's even such a thing as an optimal hormone level is unclear, notes Cynthia Pearson, executive director of the National Women's Health Network, a nonprofit group that advocates for women's health issues: "Women can have very different symptoms at the same hormone levels."

• Fad diagnoses. One of the newer anti-aging buzz phrases is adrenal fatigue. The theory behind the syndrome is that chronic stress causes a decrease in the production of adrenal hormones, which can cause fatigue and sleep issues.

But while there is a legitimate condition called adrenal insufficiency, which is diagnosed by an endocrinologist using a battery of tests, "adrenal fatigue is a bogus diagnosis," Perls says. What's more, the standard treatment -- hydrocortisone -- can lead to osteoporosis, diabetes, and organ dysfunction, says Jeffrey I. Mechanick, M.D., clinical professor of medicine, endocrinology, diabetes, and bone disease at the Mount Sinai School of Medicine.

Heavy-metal toxicity is another trendy diagnosis. The concept: Removing the body's lifetime build-up of mercury, lead, and other metals can prevent or reverse age-related conditions such as heart disease. This is often attempted through chelation therapy, in which a synthesized amino acid called EDTA is run into patients' bloodstreams; the EDTA attaches to the metals, which are then flushed out of the body with urine. The process can take 20 to 40 two- to four-hour treatments, at a cost of at least $2,500.

But while chelation therapy may benefit those with heavy-metal poisoning (a rare problem), there's zero evidence it helps the rest of us. "It's quackery at its best," Perls says. "People have died from it." Case in point: In 2003, a 53-year-old Oregon woman died during her fourth round of chelation therapy. According to the medical examiner, the cause was a cardiac arrhythmia stemming from the EDTA infusion.

• Pill-a-palooza. Forget popping a simple multi-vitamin from the drugstore. "Many anti-aging doctors sell their own lines of nutraceuticals at very high prices," Perls says. "It's a profit margin that's better than what cocaine dealers get."

Don't waste your money, says Olshansky: "The vast majority of studies say anti-aging supplements don't work." Plus, they're not required to be FDA-approved before they're sold, so there's no guarantee that they're safe or effective. "We don't know if they could help, but they could be harmful," says Winifred K. Rossi, deputy director of the Division of Geriatrics and Gerontology at the National Institute on Aging.

The good news is, no one is saying that you have to just deal with hot flashes, weight gain, or any other midlife change. Fifty-plus women may not have the biology of twentysomethings, but they can still feel vibrant, healthy, and even sexy.

"Our best advice is not very different from what our mothers told us: Maintain a healthy weight, be active, eat nutritious food, and don't smoke," Rossi says. Two key nutrients also help: calcium (get 1,200 milligrams a day, preferably from food; 1 cup of yogurt has 415 milligrams) and vitamin D (aim for 2,000 IU daily in a supplement, since it's tough to get otherwise), Goldstein says.

Then, make sure you have the right medical team in place. Most women use their OB/GYNs as their go-to, but in your 40s, consider seeing a family-practice doctor or internist, too, says Pearson: "They're qualified to handle all the routine issues that come up as women hit middle age."

This back-to-basics approach may not sound as cutting-edge as special injections or souped-up supplements, but it's time-tested and a lot less costly -- for your wallet and your health. "Many of the benefits that are associated with HGH -- you can get those with exercise, for free," says Olshansky. "You don't have to spend $12,000."